Rope-drive elevator.



D. L. LINDQUIST. ROPE DRIVE ELEVATOR.

APPLICATION FILED JANA), 1909.

Patented Aug. 24, 1909.

WITNESSES:

ATTORNEY FETCH.

DAVID L. LINDQUIST, OF YONKERS, NEW YORK.

ROPE-DRIVE ELEVATOR.

To all whom it may concern:

Be it known that 1, DAVID L. LINDQUIST, a subject of the King of Sweden, and a resident of the city of Yonkers, in the county of Westchester and State of New York, United States of America, have invented certain new and useful Improvements in Rope-Drive Elevators, of which the following is a specification.

My invention relates to friction rope drive elevators and its object is to improve upon apparatus of this class and to provide simple and efficient means for automatically increasing the tension on the traction or driving ropes of such elevators.

I will describe my invention in the following specification and point out the novel features thereof in claims.

The drawing filed herewith is a diagrammatic side elevation of an elevator made ac cording to my invention.

In the drawing, 10 designates an elevator car which may be of any desired form or construction. 11 is its hoisting cable or cables which are attached to the car and run up and over a sheave 12 situated near the upper end of the elevator shaft. The cable 11 may then be run down from sheave 12 to a point on the driving rope 23 to which it is attached at 13.

14 designates a counterweight. 15 is its supporting cable or cables which run over a sheave 16 near the upper end of the shaft and to the driving rope 23 to which. it is attached at 17.

20 designates a motor of any suitable type.

21 is a driving sheave rigidly attached to the motor-shaft 22.

The driving rope 23 is shown in the form of an endless loop which runs under the driving sheave 21 and over another sheave 24 which is situated above the sheaves 12 and 16 and mounted in a manner and for a purpose which will appear hereinafter.

30 designates a beam or channel iron which acts as a support for the overhead work of the elevator and which may be a part of the building in which the elevator is installed.

31 designates a tilting lever which is supported by beam 30 by means of a hinge-block 32. The sheaves 12 and 16 are mounted upon the tilting lever 31, one on each side of the hinge-block 32.

33, 33 designate upright beams rigidly at tached to the supporting beam 30 and to the horizontal beam 34 which they support.

Specification of Letters Patent.

Application filed January 9, 1909.

Patented Aug. 24, 1909. Serial No. 471,403.

35 and 36 are fixed projections which are attached to the horizontalbeam 34.

40 designates a secondary tilting lever which, when unaffected by external forces, rests upon the projections 35 and 36 at 41 and 42. Between these points 41 and 42 the driving-rope sheave 24 is mounted.

Attached to the tilting lever 31 at 37 and 38 are rods 43 and 44 which extend up through the auxiliary tilting lever'4O near its ends and which maybe connected to this lever through springs 45 and 46 and nuts 47 and 48 which are screwed onto the rods 43 and 44 respectively.

If the car 10 and the counterweight 14 are of equal weight the tilting lever 31 and its connected parts will ordinarily stand in the positions in which they are shown in the drawing. This same result may be obtained when there is a difference in weight between the car and the counterweight by changing the position of the hinge-block 32. When, however, the efiective weight of either the car or the counterweight is changed, the tilting lever 31 will be depressed on one side or the other. Let us, for example, say that a load is added to the car so that the end of tilting lever 31, upon which sheave 12 is mounted, is pulled down. It may be seen that this movement of tilting lever 31 will be transmitted through the rod 44 to auxiliary tilting lever 40. The right-hand end of the latter is thus pulled down and the other end is raised. That is, the auxiliary tilting lever 40 will swing on its fulcrum at 42 and will thereby cause the sheave 24 to be raised. This will exert an upward pull on the driving rope 23 and will thus increase its frictional contact with the driving sheave 21. This extra pull upon the driving rope or ropes will be exerted upon both sides of the driving loop which is obviously highly desirable. Of course an extra downward pull upon the counterweight sheave 16 will have a similar effect upon the driving rope sheave 24. It may be seen then, that the operation of this device depends .upon the difference in the effective weights of the car and the counterweight. The constant frictional contact of the driving rope or ropes on the driving sheave may be obtained in any of the well-known ways. The object of this invention is to automatically increase this frictional contact at difierent parts of the operation. During most of the operation of an elevator of this type it is necessary to have only enough tension on the driving ropes to prevent slipping of the ropes on the driving sheave when the latter is at rest or to drive a light load on the car. VVit-h my invention this tension and consequent friction is increased whenever the load in the car is increased and this increase of friction may, by proper arrangement of the parts, be made proportional to such increase of load.

In the operation of a rope drive elevator there is a change in the effective weight of the. car and the counterweight on the driving ropes whenever the elevator is started or stopped. This is due to the change in the momentum of the moving parts and causes atendency of the driving ropes to slip on the driving sheave at just such parts of the operation as such. slippage is most disadvantageous. My invention. overcomes this diiiiculty. By its use a. lower initial tension may be used on the driving ropes with a resultant increase in the efficiency and with less wear upon the driving ropes.

I have illustrated; my invention diagrammatically with no attempt at showing the details of. the working parts and with but a general approximation of the relative positions of the parts. This is because the principle herein. described and claimed may obviouslv be worked out in many ways.

What I claim is.-

L A car, a counterweight, a driving sheave, a rope held in frictional contact with.

said. sheave by the weight of the car and the counterweight, and means actuated by an increase or decrease in the effective weight of either the car or the counterweight for automatically increasing the traction of the. rope on the sheave.

2. A car, a counterweight, a driving sheave, a rope-loop held in frictional; contact with said sheave imder tension by the com.- bined weight of thecar and the counterweight, and meansv actuated by an increase or afdecrease, in the effective weight of either the caror of the counterweight for automatically increasing the tension on both sides. of said rope-loop.

3.. A car, a. counterweight, a driving sheave, a fixed support therefor, a second sheave, a movable support. for said secondv sheave, ropelo.op about both of said sheaves, and means actuated by the difference between the effective weights of the car and the counterweight for. automatically moving the second sheave to increase the tension on the rope-loop.

4. A car, a. counterweight, a driving. sheave, a rope system connecting the car and. the counterweight and associated with said driving sheave,.a sheave arranged to support the car,- a sheave. arranged to support the counterweight, a, tilting lever upon which.

the supporting sheaves are mounted, andmeans actuated by a movement of said tilting lever in either direction, for increasing the tension on the rope system.

5. A car, a counterweight, a driving sheave, a rope system connecting the car and the counterweight and associated with said driving sheave, a sheave arranged to support the can, a sheave arranged to support the counterweight, a tilting lever upon which the supporting sheaves are mounted, and a secondary lever actuated by a movement of said tilting lever in either direction, said secondary lever being arranged to increase the tension on the rope system.

6. A car, a counterweight, a driving sheave, a rope system connecting the car and the counterweight and associated-with said driving sheave, a sheave arranged. to support the car, a sheave arranged. to support the counterweight, a tilting lever upon which the supporting sheaves are mounted, a secondary lever actuated by a movement of said tilting lever in either direction, said secondary lever being arranged to increase the tension on the rope system, and resilient connections between the tilting lever and the secondary lever.

7. A car, a counterweight, a driving sheave, a rope-loop held in frictional contact with said sheave under tension by the combined weight of the car and the counterweight, a rope connecting the car with the rope, a rope connecting the counterweight with the rope-loop, a supporting sheave for said counterweight rope, a tilting lever upon I which said supporting sheaves are mounted,

and means actuated by a movement of said tilting lever in either direction, for increasing the tension on the rope system.

8. A car, a counterweight, a driving sheave, a rope-loop held in frictional contact with said sheave under tension by the combined weight of the car and the counterweight, a rope connecting the car with the rope-loop, a supporting sheave for said carrope, a rope connecting the counterweight with the rope-loop, a supporting sheavefor said counterweight rope, a tilting lever upon. which said supporting sheaves; arev mounted, and a secondary lever actuated by a movement of said tilting lever in either direction, said secondary lever being arranged to increase the tension on the rope system.

9. A car, a counterweight, a drivingsheave, a rope-loop held frictional contact with said sheave under tension by the com--.

rope, a rope connecting the counterweight; with the rope-loop, a supporting sheave forsaid counterweight: rope, a tilting. lever upon which sald supportmg sheaves are mounted,

a secondary lever actuated by a movement of said tilting lever in either direction, said secondary lever being arranged to increase the tension on the rope system, and resilient connections between the tilting lever and the secondary lever.

10. A car, a counterweight, a driving sheave, a fixed support therefor, a tension sheave, a movable support for the tension sheave, a rope-loop about both of said sheaves, a rope connecting the car with the rope-loop, a supporting sheave for said carrope, a rope connecting the counterweight with the rope-loop, a supporting sheave for said counterweight rope, a tilting lever upon which said supporting sheaves are mounted, and means for causing a movement of the tilting lever in either direction to shift the position of the tension sheave whereby the latter increases the tension on the rope-loop.

11. A car, a counterweight, a driving sheave, a fixedisupport therefor, a tension sheave, a movable support for the tension sheave, a rope-loop about both of said sheaves, a rope connecting the car with the rope-loop, a supporting sheave for said carrope, a rope connecting the counterweight with the rope-loop, a supporting sheave for said counterweight rope, a tilting lever upon which said supporting sheaves are mounted, a secondary lever upon which the movable support for the tension sheave is mounted, connections between the tilting lever and the secondary lever whereby a movement of the tilting lever in either direction, caused by a difference between the effective weight of the car and the counterweight, will shift the position of the tension sheave and thereby increase the tension in the rope-loop.

12. A car, a counterweight, a driving sheave, a rope in frictional contact with said sheave, and means dependent upon the difference between the effective weight of the car and the counterweight for automatically varying the traction of the rope on said sheave.

13. A car, a counterweight, a driving sheave, a rope in frictional contact with said sheave, and means dependent upon the difference between the effective weight of the car and the counterweight for automatically increasing the traction of the rope on said sheave in proportion to the amount of said difference.

In testimony whereof I have signed my name to this specification in the presence of two subscribin witnesses.

imvn) L. LINDQUIST. Witnesses:

JoB FISH, Jr., ERNEST W. MARSHALL. 

